Couple of A level questions

[BIOSTALL]

Hey, i have some questions on an A-Level piece of maths that i cant seem to figure out the answer to:

1. Make t the subject in P=Poe^(to the power of)0.1(t-3)

2. Sketch the graph of y=|2x+3| << i've done that bit
Hence, or otherwise, solve the equation |2x+3| = 2-x <<< need that bit

3. Find the integral of xsin2x dx

If anyone could help me with any of these i'd be so grateful

[timeshifter]

2) Graph the two seperate equations and find their intersection point(s).

[jemidiah]

1. Do you mean solve for t? If so, take the natural log of both sides and continue from there.

2. Absolute value gets rid of negative signs, so with the equation you need to solve, the 2x+3 part can be either positive or negative, and it won't matter to the rest of the equation. Hence, you split up the whole thing into two equations:
2x+3=+(2-x)
2x+3=-(2-x)
It can be a little difficult to 'see' right away, but it's there

3. Use integration by parts. There are many sites and books that give explain this method.